Allow get_comments_number() to accept post object

[coffee2code]

get_comments_number() unnecessarily enforces an int value for its $post_id argument. This is contrary to expectations whereby most template functions accept either a post object or ID, and it doesn't match up with the function's phpDocs which indicate either value is acceptable.

Ultimately, the $post_id argument gets sent to get_post() to obtain the post, so the argument can be directly passed along and left to be handled by get_post().

Attached is a patch which removes the unnecessary typecasting. The patch also adds braces to the if conditional to match the new guideline change.

Also included are some unit tests for it. Since there doesn't appear to be any unit tests for comment-template.php functions, I created tests/comment/output.php to mirror how posts template functions are tested in tests/post/output.php (though post template tests are pretty meager).

[nofearinc]

Looks good and works for me, although I think that the test should be in a separate diff.

[JanHenkG]

The fix of coffee2code also worked for me, I kept this fix unchanged in the files I attached. The changes I made are:

• Created separate patch files for the fix itself and the tests.
• Refactored the tests a bit, for example I removed the use of the $post_id member variable.

[coffee2code]

Patches still apply cleanly. Seems like an easy win.

[DrewAPicture]

The docs are already in-line with accepting either so +1 for 26240.2.diff​ minus the unnecessary brace change(s).

[wonderboymusic]

[28558] didn't paste itself here.

[ocean90]

There is a typo in the get_comments_number hook doc for the $post_id arg: Nnumber.

Also the value of $post_id has changed. Previously if $post_id was 0 $post_id was set to get_the_ID(). It seems like $post_id was never a WP_Post object so we can replace $post_id with $post->ID in the get_comments_number filter.

[ocean90]

[27156] removed the "Optional" part for $post_id, we should add it back since it's optional.

[DrewAPicture]

Replying to ocean90:

[27156] removed the "Optional" part for $post_id, we should add it back since it's optional.

Opened #28388

[DrewAPicture]

In 28602:

Fix parameter description for the $post_id argument in get_comments_number() to note that it is optional.

Also fixes the corresponding filter docs, as $post_id, not $post is passed to the filter.

See [27156]. Fixes #26240.

[ocean90]

In 28604:

Pass $post->ID to get_comments_number filter.

Also fixes indentation and a typo in corresponding filter docs.

see #26240.

[SergeyBiryukov]

This test currently fails:

1) Tests_Comment_Template::test_get_comments_number
Trying to get property of non-object

S:\home\wordpress\develop\src\wp-includes\comment-template.php:701
S:\home\wordpress\develop\tests\phpunit\tests\comment\template.php:10

26240.3.diff​ fixes it.

[wonderboymusic]

In 28638:

Fix an error caused by [28604] in get_comments_number() unit tests.

Props SergeyBiryukov.
Fixes #26240.